A pulley system has an efficiency of 74.2%. If you perform 200 J of work, how much useful work does the pulley perform?

1 answer:

7 0

Efficiency is the measure of how efficient a process is. It is used to assess the ability of a process in avoiding waste energy, materials, money and time in doing a desirable output. It is calculated as;

Efficiency = useful energy ouput / total energy input

.742 = useful energy / 200 J
Useful energy = 148.4 J <-----------OPTION B

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(ii) N = R = Normal Reaction from the ground upwards
(iii) Fe = Force of engine towards the right
(iv) f = friction towards the left
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2.2.1)
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2.3)
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2.4.1)
v = 0
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